Over the past few years, Android TV has gradually shifted from a user-focused set-top box platform to a software stack for operator partners to use. Because of that shift, Android TV might not be obvious and well-known to the general consumer, but it's more widely-used than ever. In fact, the OS now has "tens of millions of users," according to a Google executive.

Direct carrier billing is one of the most convenient ways to buy apps and content from the Play Store. Instead of making sure you have a valid credit or debit card or trying to find gift cards or setting up a Paypal account, you can simply have the purchase amount billed with your regular mobile service.

In today's round of new carrier additions on the Google Play support pages we find the French company Free, Hungarian TMI (Magyar Telekom), Indonesian Telkomsel, Slovakian PPF (O2), and Taiwanese Taiwan Mobile. Most of these won't affect a lot of subscribers (Free: 9M - TMI: 5.4M - O2: 1.7M - Taiwan Mobile: 7.6M), but Indonesia's Telkomsel is really a big deal.

It's not much of a secret that Android's success is in no small part due to the broad range of devices which are currently available on the market. There is a phone for everyone available if you look hard enough, from top-of-the-range choices such as the Samsung Galaxy S II all the way down to cheap, unbranded phones from China.

For those on a budget this choice can only be a good thing, but for carriers, it turns out that the cheaper devices may actually do more harm than good.

As Android is open source software, there are no hardware specifications that manufacturers have to meet before they can sell their phones with Google's operating system.